Light emitting diodes (“LEDs”) are employed as a basic lighting structure in a variety of forms, such as outdoor signage and decorative lighting. LED-based light strings have been used in channel lettering systems, architectural border tube applications, under cabinet lighting applications and for general illumination. A known spoolable LED light string arranges the LEDs in parallel circuitry. This parallel arrangement requires a very low voltage output power supply (Vout approximately 2.0 to 4.5 VDC) and a large amount of drive current capability. The large currents that must be delivered severely limits the distance that the power supply can be spaced from the LED strip as well as the length of the LED strip that can be driven by the power supply.
Known LED string lights also use parallel/series combinations of LEDs. These known systems require that the LEDs mount to a printed circuit board as well as some sort of current limiting device. These known systems require the printed circuit board to be environmentally isolated, which is expensive. Furthermore, the printed circuit board based systems are also difficult to spool, to mount and to cut to length in addition to requiring the expense of the printed circuit board itself.
Other known LED light strings employ a plurality of LEDs wired in a series/parallel block that are run directly off AC power. These known systems require complicated designs to account for the alternating current.
The present LED light engine contemplates an improved apparatus and method that overcomes the above-mentioned limitations and others.